Chandra People: Behind the Scenes, Continued

June 2, 2000 ::

The Chandra X-ray Center provides researchers with support that includes data processing and a science data archive. The Center is operated for NASA by the Smithsonian
Astrophysical Observatory and is situated on the campus of Harvard University.

In our continuing look at Chandra people, we focus on astrophysicists Michael Garcia and Paul Green of the Chandra X-ray Center. Michael Garcia's areas of
research interest include black holes and neutron stars. Paul Green focuses on quasars, gravitational lenses and white dwarfs.

Dr. Michael Garcia

Q:If so, Which image(s)?A: Images of M31, The Andromeda Galaxy. In particular the views of the central supermassive black hole.

Q:How are these images changing your particular area of research? (Give an example.)A:HST had found that there was a supermassive black hole in the center of M31. Chandra found that it was 'cool', ie, that it's temperature was lower than other black
holes. This was a totally unexpected result. It also raises the question: are the supermassive black holes in other galaxies also 'cool'?

Q:What would you suggest for future X-ray astronomy missions?A: Constellation - the X-ray equivalent of KECK, is a great mission. Chandra has superb mirrors, but they are relatively small.

Paul Green

Q:If so, Which image(s)?A:These are all quick snapshots of Broad Absorption Line Quasars:

FIRST J0840+3633

Q0842+3431

LBQS 1235+1807B

Q1246-0542

UM 425

Q0059-2735

Q0135-4001

Q0254-334

IRAS 07598+6508

SBSG 1542+541

while this is a binary quasar, where we are searching for a foreground optical-dark lensing galaxy cluster!

Q2345+007

Q:How are these images changing your particular area of research? (Give an example.)A:BAL QSOs might BE the long-sought Type II QSOs, and may also be the adolescent phase of quasar growth, when the radiation from near the black hole begins to blow away
surrounding gas and dust.